JP2013532195A - Printing composition and printing method using the same - Google Patents

Abstract

The present invention relates to a printing composition comprising an ionic liquid, a printing method using the same, and a pattern formed using the same.
The printing composition according to the present invention is useful for providing a fine line width pattern.

Description

  The present invention relates to a printing composition and a printing method using the same. More specifically, the present invention relates to a printing composition capable of realizing a fine line width and a printing method using the same. This application claims the benefit of the filing date of Korean Patent Application No. 10-2010-0078973 filed with the Korean Patent Office on August 16, 2010, the entire contents of which are incorporated herein.

  As a method for forming a pattern, there are an indirect pattern forming method such as a photolithography method and a direct pattern forming method such as a method of directly printing a pattern on a target substrate.

  The indirect pattern formation method can proceed through the following steps. First, a photoresist is uniformly applied to a film formed on a substrate, and this is selectively exposed and developed to form a photoresist pattern. Next, the pattern is transferred by etching the film using the photoresist pattern as a mask. Thereafter, the photoresist is removed with a stripping solution.

  Such an indirect pattern formation method uses a photoresist material and a stripping solution in addition to a film to be patterned, thereby increasing the process cost due to the cost of the photoresist material and the stripping solution and the disposal cost thereof. Bring. There is also a problem of environmental pollution associated with disposal of the material. In addition, the indirect method has many problems such as a large number of steps, a lot of time and cost, and defects in the final product when the photoresist material cannot be sufficiently removed.

  On the other hand, in the case of a method of directly printing a pattern, whether printability by drying the printing composition during the printing process has a great influence on the realization of the fine line width. Specifically, when directly printing a fine line width pattern, the line height and line width are smaller than when printing a thick line width pattern. The problem of volatilization or absorption by the silicone blanket and drying of the printing composition is maximized. If the solvent is dried too quickly into the atmosphere, a residual film is generated by drying the ink composition on the cliché during doctoring, thereby printing at the time of pattern transfer, for example, off. The problem of unevenness occurs. On the other hand, if the silicone blanket absorbs too much solvent, the printing composition on the surface of the blanket may be dried, resulting in poor transfer to the substrate during setting.

  In order to solve the problems of the prior art, an object of the present invention is to provide a printing composition capable of providing a pattern having a fine line width and a printing method using the same.

  One embodiment of the present invention provides a printing composition comprising an ionic liquid.

  Another embodiment of the present invention provides a printing method using the printing composition.

  Yet another embodiment of the present invention provides a pattern formed using the printing composition.

  Unlike conventional ink compositions, the printing composition according to the present invention has improved drying and blanket absorption problems due to volatilization of the solvent into the atmosphere, and is useful for forming fine line width patterns. Is possible.

6 is a photograph showing a printing result according to Comparative Example 1. 2 is a photograph showing a printing result according to Example 1. FIG. 6 is a photograph showing a printing result according to Example 2. 6 is a photograph showing a printing result according to Example 3. 6 is a photograph showing a printing result according to Example 3. 6 is a photograph showing a printing result according to Example 3. 6 is a photograph showing a printing result according to Example 3. 6 is a photograph showing a printing result according to Example 4; 10 is a photograph showing a printing result according to Example 5. 10 is a photograph showing a printing result according to Example 6. 6 is a photograph showing a printing result according to Comparative Example 2.

  Hereinafter, the present invention will be described in more detail.

  One embodiment of the present invention provides a printing composition comprising an ionic liquid.

  The ionic liquid includes ions or short-lived ion pairs, and refers to a substance that exists as a liquid at room temperature. This is different from a normal solvent maintaining a liquid state in an electrically neutral molecular state. In the present invention, it has been found that a printing composition capable of forming a pattern having a fine line width can be provided by adding an ionic liquid to the printing composition.

  When only a solvent is used in the printing composition, the organic solvent used for printing generally promotes drying of the ink composition by volatilization characteristics and absorption into the silicone, so that it remains when forming a pattern with a fine line width. Pattern defects are likely to occur due to film formation or uneven printing. However, in the present invention, the above-mentioned problems can be prevented by adding an ionic liquid to the printing composition.

  Further, the ionic liquid can be composed of a combination of various cations and anions, and therefore has an advantage that the physical properties can be easily adjusted. For example, the ionic liquid can be adjusted in viscosity, hydrophilicity or hydrophobicity, stability, etc. depending on the type of cation or anion. When a solvent is used together, the ionic liquid is miscible with the solvent ( miscibility) is also adjustable.

  For example, 1-methyl-3-alkyl-imidazolium hexafluorophosphate and 1-methyl-3-alkyl-imidazolium-bis (trifluoromethylsulfonyl) imide (1-methyl-3-alkyl-imidazolium hexafluorophosphate) In the case of methyl-3-alkyl-imidazolium bis (trifluoromethylsulfimide) imido, when the anion is hexafluorophosphate, the solubility in water when the anion is hexafluorophosphate is bis (trifluoromethylsulfonyl) imide. In the case of the same anion, the cation is 1-methyl-3-alkyl-imidazolium (1-methyl-3 As the length of the alkyl chain in the -alkyl-imidazolium increases, the solubility in water decreases. In addition, when 1-methyl-3-alkyl-imidazolium bis (trifluoromethylsulfonyl) imide is mixed in an acrylic resin, the migration at high temperature becomes much less as the alkyl group becomes longer. . Thus, desired physical properties can be adjusted by selecting various cation and anion pairs.

  In the present invention, it is preferable to use an ionic liquid whose vapor pressure should be neglected, hardly dried to the atmosphere, and not absorbed by the blanket material such as silicone resin. For example, when a silicone resin is used as the blanket material, the ionic liquid preferably has a high polarity that is contrary to the non-polarity of the silicone resin.

  The ionic liquid is defined as a salt that exists in a liquid state at a temperature of a melting point of 100 degrees or less so that the ionic liquid can exist as a liquid at room temperature. Preferred are room temperature ionic liquids.

  The ionic liquid preferably has a boiling point of 300 degrees or more. In this case, volatilization characteristics to the atmosphere are extremely small. This is because, generally, the vapor pressure decreases as the boiling point increases.

The ionic liquid usually has an absorbance SP of about 1 or less, more preferably 0.5 or less, in a silicone resin used as a blanket material in a printing method. The absorbency (SP) to the silicone resin can be expressed by the following formula.
SP = (length after immersion−length before immersion) / (length before immersion) × 100

Examples of the cation contained in the ionic liquid include the following, but the scope of the present invention is not limited only by these examples.
[Chemical formula 3]
[NR ¹ R ² R ³ R ⁴ ] ⁺
[Chemical formula 4]
[PR ¹ R ² R ³ R ⁴ ] ⁺
R ^{1 to} R ⁴ are each preferably an alkyl group having 10 or less carbon atoms or a group containing an ether bond or hydrogen.

Examples of the anion contained in the ionic liquid include AlCl ₄ , Cl, Br, I, NO ₃ , SO ₄ , CF ₃ COO, CF ₃ SO ₃ , BF ₄ , PF ₆ , SbF ₆ and [X ( YO _m R _f ) _n ] (R _f is a perfluoroalkyl group having 1 to 4 carbon atoms, Y is C or S, X is N or C, and the m is a group in which Y is C 1 is Y in the case of S, and 2 in the case where Y is S, and n is 2 when X is nitrogen and 3 when X is carbon). However, the range is not limited.

  The ionic liquid is preferably one having excellent compatibility with other components added to the printing composition. Preferred examples include 1-butyl-3-methyl-imidazolium acetate, 1- Ethyl-3-methyl-imidazolium acetate, 1-butyl-1-methyl-pyrrolidinium bis (trifluoromethylsulfonyl) imide, 1-butyl-3-methyl-imidazolium ethyl sulfate, 1-butyl-3- Methyl-imidazolium methanesulfonate, 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate, 1-ethyl-3-methyl-imidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1- Butyl-3-methylimidazolium tetrabore Such as a door can be used.

Among the ionic liquids, physical properties with respect to solvents having excellent solubility in isopropanol are shown in Table 1.

  The printing composition according to the present invention includes a vapor pressure indicating a degree of volatilization to the atmosphere, a degree of swelling, adhesion to a blanket or a substrate to be printed, a dryness of a final pattern, an easy printing process, etc. In view of the above, it is preferable to use it by adding it to a solvent. As examples of basic printing solvents, alcohols, ethers, ketones, and hydrocarbons can be used. Specifically, alcohols comprising methanol, ethanol, isopropanol, 1-methoxypropanol, butanol, ethylhexyl alcohol and terpineol; glycols such as ethylene glycol and glycerol; ethyl acetate, butyl acetate, methoxypropyl acetate, carb Acetates such as tall acetate, ethyl carbitol acetate; ethers comprising methyl cellosolve, butyl cellosolve, diethyl ether, tetrahydrofuran and dioxane; ketones comprising methyl ethyl ketone, acetone, dimethylformamide and 1-methyl-2-pyrrolidone Hydrocarbons such as heptane, dodecane, paraffin oil, mineral spirits, benzene, toluene and It can be used one and combinations of two or more of the mixed solvent formed by selected from the group consisting of; hydrocarbons comprising xylenes.

  When the printing composition concerning this invention further contains a solvent, it is preferable that an ionic liquid is 0.1 to 10 weight% of the whole printing composition. At this time, if the content is less than 0.1% by weight, fine line width printing is not improved, and if it exceeds 10% by weight, the physical properties of the printed matter are negatively affected.

  The printing composition according to the present invention may further include a functional material for imparting a function required for a target printing pattern. For example, the printing composition according to the present invention may further include at least one material selected from a conductive material, an insulating material, and a semiconductive material. In this case, it is preferable to select and use a cation or anion of the ionic liquid that does not react with the functional material.

  As the conductive material, an organic metal salt, metal particles, or the like can be used. For example, silver, aluminum, copper, neodymium, molybdenum, or an alloy thereof can be used. To the conductive material, an organic binder for processing, glass frit, and a blackening substance such as metal oxide, carbon black, carbon nanotube, black pigment, and colored glass frit can be further added.

  As the insulating material, a photo-curable or thermosetting resin can be used. As the photocurable resin, a resin that is cured by irradiation with ultraviolet rays or the like is used. For example, a resin composition comprising an acrylate compound having a radical reactive unsaturated bond, a resin composition comprising an acrylate compound having a radical reactive unsaturated bond and a mercapto compound, epoxy acrylate, urethane acrylate, polyester acrylate, poly Examples thereof include a resin composition in which an oligomer such as ether acrylate is applied to a polyfunctional acrylate monomer. Examples of the thermosetting resin include phenol resin, unsaturated polyester resin, epoxy resin, polyurethane resin, silicone resin, and polyimide resin.

  As the semiconductor material, for example, a compound having a single metal oxide or a perovskite structure can be used as an oxide optical semiconductor. Single metal oxides include titanium, tin, zinc, iron, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, or tantalum oxide. Examples of the compound having a perovskite structure include strontium titanate, calcium titanate, sodium titanate, barium titanate, and potassium niobate.

  The printing composition comprising the ionic liquid according to the present invention can further comprise a solvent and a functional material.

  The printing composition comprising the ionic liquid, the solvent and the functional material is 0.01 to 10% by weight of the ionic liquid and 5 to 80% by weight of the solvent based on the total weight of the printing composition. And the functional material may comprise 15 to 90% by weight.

  At this time, if the content of the ionic liquid is less than 0.1% by weight, fine line width printing is not improved, and if it exceeds 10% by weight, the physical properties of the printed matter are negatively affected. In addition, when the content of the solvent is less than 5% by weight, the viscosity is too high to perform the printing process, and when it exceeds 80% by weight, the viscosity is too low to perform the printing process, and the printing ink It is difficult to have a function as. In addition, when the content of the functional material is less than 15% by weight, it is difficult to perform the function as a printing ink. When the content exceeds 90% by weight, the printing ink cannot be produced, and furthermore, the viscosity is too high to perform printing. Can not.

  The printing composition according to the present invention preferably has a viscosity of 3 cps to 30,000 cps.

  Another embodiment of the present invention provides a printing method using the printing composition. The printing method that can be used in the present invention is not particularly limited, and gravure, gravure offset, reverse offset, ink jet method, or the like can be used. In the printing method, a roll type or a plate type is used. Is possible.

  For example, in reverse offset printing, a paste is applied to a roll-type blanket, and then a desired pattern is formed on the blanket by bringing the paste into close contact with an uneven cliche, and then the pattern formed on the blanket is formed into a conductive film. It is possible to carry out by a method of transferring to. Alternatively, gravure offset printing is performed by filling a paste on an intaglio engraved with a pattern, then performing primary transfer with a silicone rubber called a blanket, and bringing the blanket and a substrate on which a conductive film is formed into close contact. It can be carried out by a secondary transfer method. The intaglio can be manufactured by precision etching of a substrate. The intaglio may be manufactured by etching a metal plate, or may be manufactured by optical patterning via a polymer resin. Gravure printing can be performed by a method in which a blanket with a pattern cut is wound on a roll to fill the pattern with a paste, and then transferred to a substrate on which a conductive film is formed. In the present invention, not only the above methods can be used alone, but also the above methods may be used in combination.

  Yet another embodiment of the present invention provides a pattern formed using the printing composition.

  The pattern formed according to the present invention is characterized by having a particle property. Here, the term “particulate” means that the functional material constituting the pattern exists in the particle state as it is, or the particles exist in a necking state. This is in contrast to the fact that the constituents of the pattern are not present in the form of particles, as in the case of using vapor deposition methods.

  The ratio of the line width to the line height (line height / line width) of the pattern formed according to the present invention is preferably 0.3 or less. The line width of the pattern can be 100 micrometers or less, preferably 0.1 to 30 micrometers, more preferably 0.5 to 20 micrometers, and still more preferably 1 to 15 micrometers. The line height of the pattern can be 6 micrometers or less, preferably about 4 micrometers or less.

[Example]
EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, the following Example is for demonstrating this invention and is not for limiting the scope of the present invention.

Example 1
Nanosilver paste (Nanosilver 20 nm 70%, solvent 30%; solvent is a mixture of alpha-terpineol and BCA (butyral carbitol acetate) and total weight 1-butyl-1-methylpyrrolidinium bis (trifluoromethylsulfonyl) A printing composition comprising 5% by weight of imide (viscosity 6000 cps) was printed in a gravure offset manner at a relative humidity of 44%, at which time the time between set after off (hereinafter referred to as “set”). Waiting time: Off means transferring all the paste on the cliche to the silicone blanket, and setting means transferring the paste on the blanket to the substrate. 0 seconds is the waiting time immediately before starting) The there was. Printing result shown in FIG.

Example 2
The same operation as in Example 1 was performed except that the waiting time was 30 seconds. The printing result is shown in FIG. Despite the waiting time of 30 seconds, it can be confirmed that the printing state is good.

Example 3
The waiting time was fixed at 0 second, and the composition of the ionic liquid was changed to 0.1, 0.5, 1, and 5%, and printing was performed in the same manner as in Example 1. The printing results are shown in FIGS. It was confirmed that the printing state was good within the range of the composition.

Example 4
The experiment was conducted in the same manner as in Example 1 except that the ionic liquid was changed to 1-butyl-3-methyl-imidazolium tetraborate. The experimental results after the addition are shown in FIG. It can be confirmed that the printing state is improved after the addition of the ionic liquid.

Example 5
The experiment was conducted in the same manner as in Example 1 except that the ionic liquid was changed to 1-ethyl-3-methyl-imidazolium tetrafluoroborate. The experimental results after the addition are shown in FIG. It can be confirmed that the printing state is improved after the addition of the ionic liquid.

Example 6
The experiment was conducted in the same manner as in Example 1 except that the ionic liquid was changed to 1-butyl-3-methyl-imidazolium hexafluorophosphate. The experimental results after the addition are shown in FIG. It can be confirmed that the printing state is improved after the addition of the ionic liquid.

Comparative Example 1
The same procedure as in Example 1 was performed except that 1-butyl-1-methylpyrrolidinium bis (trifluoromethylsulfonyl) imide, which is an ionic liquid, was not used. The printing result is shown in FIG. Although the waiting time is set to 0 seconds, it can be confirmed that a printing failure has occurred.

Comparative Example 2
The same procedure as in Example 1 was performed except that propanolamine was used in place of 1-butyl-1-methylpyrrolidinium bis (trifluoromethylsulfonyl) imide, which is an ionic liquid. The printing result is shown in FIG. Although the waiting time is set to 0 seconds, it can be confirmed that a printing failure has occurred. The SP of propanolamine was 8.

Claims (21)

  A printing composition comprising an ionic liquid.   The printing composition according to claim 1, further comprising a solvent.   The printing composition according to claim 2, wherein the ionic liquid is 0.1 to 10% by weight of the whole printing composition.   Alcohols comprising methanol, ethanol, isopropanol, 1-methoxypropanol, butanol, ethylhexyl alcohol and terpineol; glycols such as ethylene glycol, glycerin; ethyl acetate, butyl acetate, methoxypropyl acetate, carbitol Acetates, acetates such as ethyl carbitol acetate; ethers comprising methyl cellosolve, butyl cellosolve, diethyl ether, tetrahydrofuran and dioxane; ketones comprising methyl ethyl ketone, acetone, dimethylformamide and 1-methyl-2-pyrrolidone Hydrocarbons such as heptane, dodecane, paraffin oil, mineral spirits, benzene, toluene and Hydrocarbons comprising xylene; characterized in that it is a one or these two or more mixed solvents formed by selected from the group consisting of printing composition of claim 2.   The printing composition according to claim 1, further comprising a functional material.   The printing composition according to claim 5, wherein the functional material further comprises at least one of a conductive material, an insulating material, and a semiconductive material.   The printing composition according to claim 1, further comprising a solvent and a functional material.   Based on the total weight of the printing composition, the ionic liquid comprises 0.01 to 10 wt%, the solvent 5 to 80 wt%, and the functional material 15 to 90 wt%. The printing composition according to claim 7, wherein   The printing composition according to claim 1, wherein the ionic liquid has a melting point of 100 ° C. or less.   The printing composition according to claim 1, wherein the boiling point of the ionic liquid is 300 ° C. or more. The printing composition according to claim 1, wherein the ionic liquid has an absorbance (SP) of about 1 or less in a silicone resin represented by the following formula.
[formula]
SP = (length after immersion−length before immersion) / (length before immersion) × 100 The printing composition according to claim 1, wherein the ionic liquid comprises one or more cations represented by the following chemical formulas 1 to 4.
[Chemical formula 3]
[NR ¹ R ² R ³ R ⁴ ] ⁺
[Chemical formula 4]
[PR ¹ R ² R ³ R ⁴ ] ⁺
(R ^{1 to} R ⁴ are each an alkyl group having 10 or less carbon atoms or a group containing an ether bond or hydrogen.) The ionic liquid comprises AlCl ₄ , Cl, Br, I, NO ₃ , SO ₄ , CF ₃ COO, CF ₃ SO ₃ , BF ₄ , PF ₆ , SbF ₆ and [X (YO _m R _f ) _n ] ( In the formula, R _f is a C 1-4 perfluoroalkyl group, Y is C or S, X is N or C, and the m is 1 when Y is C. In the case where Y is S, it is 2 and n includes at least one anion selected from the group consisting of 2 when X is nitrogen and 3 when X is carbon. The printing composition according to claim 1, wherein:   The ionic liquid is 1-butyl-3-methyl-imidazolium acetate, 1-ethyl-3-methyl-imidazolium acetate, 1-butyl-1-methyl-pyrrolidinium bis (trifluoromethylsulfonyl) imide, 1-butyl-3-methyl-imidazolium ethyl sulfate, 1-butyl-3-methyl-imidazolium methanesulfonate, 1-butyl-3-methyl-imidazolium trifluoromethanesulfonate, 1-ethyl-3-methyl-imidazole It is characterized by comprising one or more selected from the group consisting of lithium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium hexafluorophosphate and 1-butyl-3-methylimidazolium tetraborate Item 2. The printing composition according to Item 1.   The printing composition according to claim 1, wherein the printing composition has a viscosity of 3 cps to 30,000 cps.   A printing method comprising the step of printing the printing composition according to any one of claims 1 to 15 on a substrate.   The printing method according to claim 16, wherein gravure, gravure offset, reverse offset or ink jet method is used.   It forms using the printing composition as described in any one of Claims 1-15, The pattern characterized by the above-mentioned.   The pattern according to claim 18, wherein the pattern has a particle property.   The pattern according to claim 18, wherein a ratio of a line width to a line height (line height / line width) of the pattern is 0.3 or less. The line width of the pattern is 0.1 to 30 micrometers,
The pattern according to claim 18, wherein the line height of the pattern is 6 micrometers or less.